Show artist external links

lib/music_library_web/live/artist_live/show.ex

@@ -205,6 +205,7 @@ defmodule MusicLibraryWeb.ArtistLive.Show do
     |> assign(:current_section, :artists)
     |> assign(:artist, artist)
     |> assign(:artist_info, artist_info)
+    |> assign(:external_links, external_links(artist_info))
     |> assign(:country, ArtistInfo.country(artist_info))
     |> assign_async(:lastfm_artist_info, fn ->
       with {:ok, lastfm_artist_info} <- LastFm.get_artist_info(artist.musicbrainz_id, artist.name) do
@@ -362,4 +363,20 @@ defmodule MusicLibraryWeb.ArtistLive.Show do
       attributes: [class: "mt-2 text-sm/7"]
     )
   end
+
+  @external_link_patterns %{
+    "ProgArchives" => "progarchives.com"
+  }
+
+  defp external_links(artist_info) do
+    Enum.reduce(@external_link_patterns, [], fn {name, pattern}, acc ->
+      case ArtistInfo.relation_urls(artist_info, pattern) do
+        [] ->
+          acc
+
+        [url | _rest] ->
+          [%{name: name, url: url} | acc]
+      end
+    end)
+  end
 end